Astronomy Club of Asheville February 2018 Sky Events

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1 February 2018 Sky Events The Planets this Month page 2 The Gibbous Moon Joins Jupiter, Mars and Antares page 7 A Crescent Moon Pairs with Venus page 8 Conjunction of Near Full Moon with Regulus page 9 Planet Highlights page 10 Moon Phases in February page 13 The Zodiacal Light page 14

2 February 2018 Sky Events the Planets With evening skies bereft of bright planets for nearly three months, Venus gradually emerges from its recent superior conjunction with the Sun to shine as the Evening Star in February. Despite glowing at magnitude -3.9, spotting the bright planet may be challenging. Lost in twilight s glow until mid-month, Venus remains close to the Sun and observation will require an unobstructed view low to the western horizon, no more than 30 to 45 minutes after sunset. Venus won t truly dazzle until March. Mercury is quickly moving toward its own superior solar conjunction on February 17 th and is therefore lost in the Sun s glare this month.

3 February 2018 Sky Events the Planets Faint 6 th magnitude Uranus, found in the constellation Pisces, is still visible in the southwest as evening twilight ends. Observers will enjoy at least two hours of good telescopic views in February before the distant gas giant begins to descend too low to the horizon for crisp views in the eyepiece. Neptune is moving toward its early March solar conjunction (on the other side of the Sun as seen from Earth) and is therefore beginning to be devoured by evening twilight. Those with telescopic ambitions should strive to observe the planet in the first few days of February before Neptune concedes its favorable position in the sky.

4 February 2018 Sky Events Uranus and Neptune Charts courtesy of Sky & Telescope The motion of the two ice giants, Uranus and Neptune, as they slowly move through Pisces and Aquarius, respectively, in 2018.

5 February 2018 Sky Events Uranus and Neptune Uranus and Neptune remain viable telescopic objects in February. Use the below charts to find their small, distant blue disks in a telescope this month. Uranus Charts courtesy of Sky & Telescope Neptune

6 February 2018 Sky Events the Planets Jupiter rises in the E-SE after 2:00 a.m. as February begins. The largest planet in the solar system benefits greatly as the month progresses, and by the end of February Jupiter can be seen rising shortly after midnight. Find the yearly star situated in the constellation Libra, glowing at magnitude Mars rapid easterly motion prevents the Red Planet from gaining time on the Sun throughout the month; Mars appears only 30 minutes earlier by the end of February. Catch Mars by 4:30 each morning as it moves through the dense galactic Milky Way regions located in Scorpius and Ophiuchus. Saturn is found in the SE, rising well after Jupiter and Mars. The ringed planet won t be high enough for crisp telescopic views until after 5:00 a.m., and seen lingering through the teapot of Sagittarius.

7 February 2018 Sky Events the Planets The Waning Gibbous Moon Joins Jupiter, Mars and the star Antares On the mornings of Wednesday, February 7 th through Friday, February 9 th, about 6:30 a.m., look south to view a pleasing quartet of objects: the waning gibbous Moon, bright Jupiter, the planet Mars and the bright star Antares, the heart of the Scorpion in the constellation Scorpius. Separated by less than 6, Mars and Antares are particularly interesting, for the star name Antares (a Greek word) literally means the rival of Mars due to its similar reddish color! The path of the ecliptic periodically aligns Mars near its rival, allowing us to compare these two competing celestial objects! Compare the colors of Mars and Antares which seems redder or deeper orange? Is the red supergiant star Antares a worthy rival? Image courtesy of Sky & Telescope

8 February 2018 Sky Events the Planets A Crescent Moon Pairs With Venus On the evenings of Friday through Sunday, February 16-18, a thin crescent Moon heralds the return of Venus to the evening sky. Image courtesy of Sky & Telescope Looking very low to the W-SW horizon, about 6:30 p.m., try your luck spotting these two objects in dusk s twilight. With a narrow window to accomplish this task before the pair set, binoculars will greatly improve your chances of success.

9 February 2018 Sky Events the Planets Conjunction of the Near Full Moon with Regulus Late on the evening of Wednesday, February 28 th and into the early hours of Thursday March 1 st, a waxing gibbous Moon will make a close approach to the bright star Regulus in the constellation Leo. Those who live in northern North America (Maine, Nova Scotia and other parts of Canada) will witness a lunar occultation of Regulus with the Moon passing in front of the star. From Asheville skies, however, the pair will be separated by less than ¼ of a degree, forming a very close conjunction, which occurs about 1:00 a.m. on the morning of March 1 st. Image courtesy of Sky & Telescope

10 February 2018 Planet Highlights Planet Distance from Earth Constellation(s) Diameter in arc seconds Magnitude Comments Page 1 of 3 Mercury 1.4 AUs Venus 1.7 AUs Mars 1.5 AUs Capricornus & Aquarius Capricornus & Aquarius Scorpius & Ophiuchus Reaches superior conjunction on the 17 th ; lost in the Sun s glare Reappears in evening skies late this month Found in the E- SE about four hours before sunrise.

11 February 2018 Planet Highlights Planet Distance from Earth Constellation(s) Diameter in arc seconds Magnitude Comments Page 2 of 3 Jupiter 5.3 AUs Saturn 10.6 AUs Uranus 20.4 AUs Libra Rises in the east by midnight at month s end. Sagittarius Found in the SE in pre-dawn hours. Pisces Seen in the west, observe it early after dusk this month.

12 February 2018 Planet Highlights Planet Distance from Earth Constellation(s) Diameter in arc seconds Magnitude Comments Page 3 of 3 Neptune 30.9 AUs Aquarius Heading towards conjunction with the Sun (other side of the Sun as seen from Earth) on Mar. 4 th.

13 The Moon February 2018 Last Quarter 7 th 10:54 a.m. New Moon 15 th 4:05 p.m. First Quarter** 23 rd 3:09 a.m. ** No full Moon phase this month Unless otherwise indicated, all times are EST

14 February 2018 Highlight The Zodiacal Light The first two weeks of February 2018 are ideal to find the elusive zodiacal light in the early evening sky. But what is zodiacal light? Zodiacal light is the sunlight reflected from numerous dust grains located along the plane of the solar system the ecliptic or zodiac. These dust grains are left over from the formation of the solar system (a type of cosmic dust), and their supply is continuously fed by particles from comets and asteroid collisions. The ecliptic is nearly vertical to the horizon this month, providing good viewing opportunities.

15 February 2018 Highlight The Zodiacal Light Look for the Zodiacal Light low in the west (with an unobstructed view) beginning about 80 minutes after sunset. The viewing window closes about 2 hours after sunset. Pick a very dark location far from artificial lights and without moonlight. This spring s zodiacal light will form a cone of pale light that points up from the western horizon, along the ecliptic (zodiac), toward and through the planet Mars. The best evenings without moonlight this month to see the zodiacal light will be from February 2 th 16 th. In the fall, when it is visible in the eastern morning sky, it is often called the false dawn.

16 February 2018 Highlight The Zodiacal Light Zodiacal Light and the Milky Way

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